Sneaky Crayola Paints

Feb

2008

Sneaky Crayola Paints

As a result of doing some spectrometry studies today, I found out something that a few people might find somewhat interesting. I'm trying to find something with a measurable optical absorbance in the spectrum between 700 and 800 nm. That basically means something green in color. So I thought to use Crayola watercolor paints. They've got 16 colors to a pack, so they pretty much have everything in the color wheel spectrum. However, when I tested the paints diluted in water, this is what I found.

All the colors have pretty much the same absorbance peaks: One at 400nm, and the other around 625nm. What does this mean, you ask? It means that Crayola is smart and sneaky at the same time. They don't waste money making 16 different paint compounds. They only make two paint compounds and mix different ratios of them and through spectrum superposition, they obtain a color that the eye perceives as "blue" or "green". Suffice it to say, my cheap and ghetto idea of using Crayola paints didn't work.